Jiang, John

Background: Losmapimod is an orally administered small molecule and selective p38α/β mitogen-activated protein kinase (MAPK) inhibitor able to reduce aberrant expression of DUX4 in vitro and thereby potentially slowing disease progression in patients with facioscapulohumeral muscular dystrophy (FSHD). Objective: This global, randomized, placebo-controlled, double-blind phase 3 study in patients with FSHD1 and FSHD2 examined the efficacy and safety of losmapimod over a 48-week treatment period compared to placebo (NCT05397470, EUDRACT 2022-000389-16). Methods: The primary endpoint was change in quantification of reachable workspace (RWS) expressed as relative surface area (RSA). Other endpoints included measures of muscle composition (fat content and lean muscle) using magnetic resonance imaging (MRI), muscle strength using quantitative dynamometry, and quality of life measures. Results: 130 participants received losmapimod and 130 participants received placebo, with 252 participants completing the 48-week treatment period. There were no statistically significant differences between groups in change in RSA and all secondary efficacy endpoints from baseline to Week 48. Losmapimod treatment was well-tolerated, and most adverse events were mild. Conclusions: Losmapimod was generally well tolerated with a favorable safety profile at a dose of 15 mg twice daily. Although none of the efficacy endpoints were met, study design and data from the study may inform future studies of FSHD therapies.

Summary Background Coeliac disease, an autoimmune disorder triggered by gluten ingestion, is managed by a gluten‐free diet ( GFD ), which is difficult for many patients. Larazotide acetate is a first‐in‐class oral peptide that prevents tight junction opening, and may reduce gluten uptake and associated sequelae. Aim To evaluate the efficacy and tolerability of larazotide acetate during gluten challenge. Methods This exploratory, double‐blind, randomised, placebo‐controlled study included 184 patients maintaining a GFD before and during the study. After a GFD run‐in, patients were randomised to larazotide acetate (1, 4, or 8 mg three times daily) or placebo and received 2.7 grams of gluten daily for 6 weeks. Outcomes included an experimental biomarker of intestinal permeability, the lactulose‐to‐mannitol ( LAMA ) ratio and clinical symptoms assessed by Gastrointestinal Symptom Rating Scale ( GSRS ) and anti‐transglutaminase antibody levels. Results No significant differences in LAMA ratios were observed between larazotide acetate and placebo groups. Larazotide acetate 1‐mg limited gluten‐induced symptoms measured by GSRS ( P = 0.002 vs. placebo). Mean ratio of anti‐tissue transglutaminase IgA levels over baseline was 19.0 in the placebo group compared with 5.78 ( P = 0.010), 3.88 ( P = 0.005) and 7.72 ( P = 0.025) in the larazotide acetate 1‐, 4‐, and 8‐mg groups, respectively. Adverse event rates were similar between larazotide acetate and placebo groups. Conclusions Larazotide acetate reduced gluten‐induced immune reactivity and symptoms in patients with coeliac disease undergoing gluten challenge and was generally well tolerated; however, no significant difference in LAMA ratios between larazotide acetate and placebo was observed. Results and design of this exploratory study can inform the design of future studies of pharmacological interventions in patients with coeliac disease.